Palynology of Deep Sea Cores from DSDP Site 275, Southeast Campbell Plateau

Abstract

Site 275 is located near the southeast margin of the Campbell Plateau about 600 km southeast of New Zealand and the same distance east-northeast of Campbell Island. The present depth of the sea floor is 2800 m. Five cores were recovered from the site with a total penetration of 62 m. Core 1 (4 samples), Core 2 (6 samples), Core 4 (1 sample), and Core 5 (1 sample) were examined for palynomorphs. The stratigraphic succession has been dated as Late Cretaceous and divided into two main lithological units, which are covered by a thin veneer of foraminiferal ooze and manganese nodules, of Pleistocene age. The upper unit (Unit 1) is comprised of a pale yellow and olive, soft, moderate to intense mottled sandy silt and glauconite-rich radiolarian diatom ooze. This includes all of Core 1 and all except the base of Core 2. Unit 2 is a dark olive-gray massive stiff, glauconite and nodule-bearing detrital clay silt. This unit includes the lowest section, Sample 2, CC, and all of cores 3, 4, and 5. A sharp contact separates units 1 and 2. Samples of ca 15-20 g were processed by using a standard HF/oxidation/flotation technique. Residues were mounted in safranin glycerine jelly. (auth/EB)